(1) Field of the Invention
The present invention relates to a terminal fitting to be electrically connected to an electric wire.
(2) Description of the Related Art
Various electronic instruments are mounted on a motor vehicle. In a motor vehicle, wiring harness is mounted in order to transfer electric power from a power source to the electronic instruments and to transfer a signal from a computer to the electronic instruments. The wiring harness includes a plurality of electric wires (hereinafter, wires) 101 (only one wire being shown in FIGS. 22A, 22B and 22C by its cross sectional view) tied up in a bundle with each other and terminal fittings attached to the end of the wires 101. The wire 101 includes an electrically conductive (hereinafter, conductive) core wire 102 and an insulating coating 103 which coats the core wire 102. The terminal fitting is formed by bending a conductive metal plate. The terminal fitting is electrically connected to the core wire 102 of the wire 101.
As the terminal fitting, a pressure-welding terminal 100 shown in FIG. 20 may be utilized. As shown in FIGS. 20 and 21, the pressure-welding terminal 100 has a plurality of pressure-welding members 104. Each pressure-welding member 104 includes a pair of pressure-welding blades 105, 106. As shown in FIGS. 22A, 22B and 22C, in the pressure-welding terminal 100, a wire 101 is press-fit into between the pressure-welding blades 105 and 106 and then, the blades 105 and 106 cut the coating 103 so as to come in contact with the core wire 102, thereby the pressure-welding terminal 100 is electrically connected to the wire 101.
As for the conventional pressure-welding terminal 100 described above, when the wire 101 is press-fit into between the pressure-welding blades 105 and 106, as shown in FIG. 22C, the pressure-welding terminal 100 possibly is plastically deformed in the direction, in which the distance between the pressure-welding blades 105 and 106 increases. If the distance between the pressure-welding blades 105 and 106 increases, each inner edge of the pressure-welding blades 105 and 106 possibly does not come in contact with the core wire 102 of the wire 101. That is, there has been a problem that the electric connection between the conventional pressure-welding terminal 100 and the wire 101 is possibly not secured.
It is therefore an objective of the present invention to solve the above problem and to provide a terminal fitting, which securely can be electrically connected to an electric wire.
In order to attain the above objective, the present invention is to provide a terminal fitting comprising:
a bottom wall, on a surface of which an electric wire consisting of a core wire and a coating is placed;
a pair of pressure-welding blades arranged in parallel with each other arising from the bottom wall, each pressure-welding blade including an inner edge for cutting the coating of the electric wire; and
a projection formed on an end of the inner edge of each pressure-welding blade near to the bottom wall, protruding from the end toward the length direction of the electric wire,
wherein the electric wire is press-fit into between the pair of pressure-welding blades, which cuts the coating of the electric wire so as to come in contact with the core wire of the electric wire.
With the construction described above, when the wire is press-fit into between the blades, the wire comes in contact with the projection since the projection is formed on the end of the blade near to the bottom wall. Then, the wire pushes the projection toward the bottom wall. Since the projection is formed on the end of the blade, the blades are displaced in the direction, in which both ends situated at far side from the bottom wall approach each other. That is, the distance between both blades decreases.
Further, the projection protrudes from the end along the length direction of the wire. Therefore, the projection is prevented from coming in contact with the core wire of the wire. That is, the core wire is prevented from being damaged.
Therefore, the distance between both blades is prevented from increasing when the wire is press-fit into between both blades. Each blade securely comes in contact with the core wire, thereby each blade is securely connected electrically to the wire.
Preferably, each projection protrudes in the same direction from the corresponding end.
With the construction described above, when the wire is press-fit into between both blades, the projection securely comes in contact with the wire. Therefore, each blade more securely comes in contact with the core wire and is more securely connected electrically to the wire.
In order to attain the above objective, the present invention is also to provide a terminal fitting comprising:
a bottom wall, on a surface of which an electric wire consisting of a core wire and a coating is placed;
a pair of side walls arising from both edges of the bottom wall; and
first and second pressure-welding members to be pressure-welded to the electric wire, each of which has a pair of pressure-welding blades and a projection protruding from an end of an inner edge of each pressure-welding blade near to the bottom wall, each pressure-welding blade including the inner edge for cutting the coating of the electric wire, and the projection being formed at the end of the inner edge of one pressure-welding blade of the first pressure-welding member near to the bottom wall and formed at the end of the inner edge of the opposite pressure-welding blade of the second pressure-welding member near to the bottom wall,
wherein the one pressure-welding blade continues to one side wall while the opposite pressure-welding blade continues to the opposite side wall, and the electric wire is press-fit into between the pair of pressure-welding blades which cuts the coating of the electric wire so as to come in contact with the core wire of the electric wire.
With the construction described above, the wire press-fit into between both blades comes in contact with the projection and pushes the projection toward the bottom wall. Then, both blades are displaced in the direction, in which both ends of the blade situated at far side from the bottom wall approach each other. Therefore, the distance between the pair of side walls can be prevented from increasing and the distance between the pair of blades can be prevented from increasing. Therefore, each blade more securely comes in contact with the core wire and is more securely connected electrically to the wire.
Preferably, the projection protrudes from the end in the length direction of the electric wire.
With the construction described above, when the wire is press-fit into between the pair of blades, the core wire of the wire can be prevented from coming in contact with the projection. Therefore, the core wire can be prevented from being damaged. Each blade can be more securely connected electrically to the wire.
Preferably, protrusion length of the projection from the end gradually increases as the projection approaches the bottom wall.
With the construction described above, when the wire is press-fit into between the blades, the wire comes in contact with the projection since the projection is formed on the end of the blade near to the bottom wall. Then, the wire pushes the projection toward the bottom wall. Since the projection is formed on the end of the blade, the blades are displaced in the direction, in which both ends situated at far side from the bottom wall approach each other. That is, the distance between both blades decreases. Therefore, each blade more securely comes in contact with the core wire and is more securely connected electrically to the wire.
Preferably, protrusion length of the projection from the end gradually increases as the projection leaves the bottom wall.
With the construction described above, even when the wire is press-fit into between both blades and the wire comes in contact with the projection, the protrusion length of the projection from the blade can be prevented from decreasing.
Therefore, the wire can securely push the projection toward the bottom wall and the distance between both blades can be prevented from increasing when the wire is press-fit into between both blades. Therefore, each blade more securely comes in contact with the core wire and is more securely connected electrically to the wire.